Two-way flushing device for treatment of hydrocephalus



July 1, 1969 R. H. AMES 3,452,757

TWOWAY FLUSHING DEVICE FOR TREATMENT 0F 'HYDROCEPHALUS Filed Sept. 14, 1966 I l IIIIIIIII y INVENTOR.

Richard/i fime QTTORNEY United States Patent US. Cl. 128350 4 Claims ABSTRACT OF THE DISCLOSURE There is described herein a surgical hydrocephalus treatment device comprising a flushing unit interposed between a ventricular catheter and an outlet catheter, the flushing device having a pair of blister-shaped resilient chambers interconnected by a tubular member extending between the approximate centers of the two chambers whereby digital pressure applied to either chamber also acts to collapse the end of the tubular member which lies in that chamber.

The present invention relates to valving devices, and more particularly to surgically implantable valves .adapted for operation by the fingers.

In the treatment of hydrocephalus, commonly known as water on the brain, it is now a fairly common practice to drain cerebrospinal fluid from the brain ventricle by means of a catheter. One end of the catheter is intro duced into the ventricle and the other end is arranged to drain either into the blood circulating system or to the peritoneal cavity. The entire device is, in the usual case, surgically implanted beneath the skin of the patient. Valves of some type are generally provided at the outlet end of the catheter to :allow only unidirectional flow.

Such devices for the treatment of hydrocephalus have up until the present time suffered from a possibility of blockage by tissue particles carried in the fluid. Several devices have been developed in an attempt to overcome this difliculty. However, each suffers from inherent disadvantages, a primary one being that most such devices operate only in one direction thus tending to make any large obstruction worse.

It is an object of the present invention to provide an improved flushing device for use in hydrocephalus shunts.

A further object is the provision of a hydrocephalus shunt system in which flushing in either direction may be easily accomplished.

In accordance with these and other objects there is provided by the present invention a hydrocephalus shunt having provision for two-way flushing operation and, in the case of a large obstruction, means for easily determining whether the ventricular catheter or the drainage catheter is clogged, thus necessitating any need for removing the entire device. The flushing device is placed under the skin adjacent the skull of the patient, and the device is easily manipulated with the fingers to check for blockage and to act as -a pump and valve for flushing.

Other objects and attendant advantages will become obvious to those skilled in the art from a consideration of the following detailed description when read in connection With the accompanying drawings wherein:

FIG. 1 is a partly diagrammatic view showing a hydrocephalus shunt assembly in place in a patient;

FIG. 2 is a top view of the base portion of a shunt flushing device made in accordance with the present invention; and

FIG. 3 is a cross-sectional view of a completed flushing device of the type shown in FIG. 2.

Patented July 1, 1969 Referring now to the drawings wherein like reference numerals refer to corresponding parts throughout the figures thereof, there is shown in FIG. 1 a hydrocephalus shunt consisting of a ventricular catheter 11, a flushing assembly 12, and an outlet catheter 13. All parts of the shunt are made of flexible material such as silicone rubber. The ventricular catheter 11 is provided at a point spaced from the flushing assembly with a right angle bend 14 at which point the catheter extends through a burr hole 16 in the skull of the patient into the brain ventricle to drain excess cerebrospinal fluid therefrom. The flushing assembly 12 which will be described in detail hereinafter is connected to the ventricular catheter and is designed to be inserted under the skin of the patient, overlying the skull a distance away from the bend 14 in the ventricular catheter. The outlet catheter 13 is in turn connected to the flushing assembly 12 and is surgically implanted to drain either into the peritoneal cavity or the blood circulatory system through a valve 17. The valve 17 may, for example, be merely a slit in the catheter at or near its distal end. The slit opens upon application of a very small amount of positive pressure from within, as compared with the external pressure, to allow fluid to drain from the catheter. Conversely, upon application of higher pressure outside of the catheter than inside, the slit is forced to a closed position and blocks any backflow of fluid into the catheter from the area surrounding it.

The flushing device 12, as shown in greater detail in FIGS. 2 and 3, comprises a pair of circular recesses 18 and 19 in an oblong baseplate or backing member 21. The recesses 18 and 19 are covered by thin blister-shaped members 22 and 23, respectively, thereby forming a pair of spaced, closed chambers.

The chambers are interconnected by a length of thinwalled flexible tubing 24 which has sufficient length to extend to the approximate center of both chambers. Additionally, one of the chambers (hereinafter referred to as the proximal chamber) is interconnected with the ventricular catheter 11 and the other of the chambers (hereinafter referred to as the distal chamber) is interconnected with the outlet catheter 13. Both connections are preferably in the plane of the baseplate for reasons which will become apparent hereinafter.

The two catheters 11 and 13 and the flushing device 12 may be formed from any suitable material which is inert within the human body such as silicone rubber, for example, and may be made as a single unit. Alternatively, the flushing device and the tWo catheters may be manufactured separately, assembled by the use of suitable connectors and sealed with a medical-grade adhesive.

In operation, after implantation into the body as described with respect to FIG. 1, fluid is drained from the brain ventricle into the ventricular catheter, passes from the ventricular catheter into the proximal chamber of the flushing device, through the tube 24 into the distal chamber and out of the distal chamber into the outlet catheter. When sufiicient differential pressure is reached across the outlet valve 17 of the outlet catheter, the outlet valve opens allowing the fluid to flow out of the outlet catheter into either the peritoneal cavity or the blood circulatory system, depending upon where the outlet catheter is implanted.

When the device is to be checked for operation, the blister-shaped members covering the chambers of the flushing device can be felt and manipulated through the skin of the patient. The skull of the patient and the backing member 21 form a relatively rigid base for the two chambers to allow compression of the chambers. The proximal chamber is compressed with a finger to the extent necessary to pinch the end of the tube 24 which protrudes to the approximate center of the chamber. If the proximal chamber can be readily compressed, it is obvious that at least one end of the shunt is clear of obstruction; that is, fluid is free to flow out of either the ventricular catheter or the outlet catheter, or both.

With the proximal chamber compressed, finger pressure is then applied to the blister-shaped member covering the distal chamber. If the distal chamber collapses readily, it is obvious that the outlet catheter is unobstructed and functioning properly. Conversely, failure of the distal chamber to collapse readily indicates an obstructed outlet catheter.

To check the operation of the ventricular catheter a reverse procedure is followed. The distal chamber is first compressed to the point where the tube 24 is sealed, then pressure is applied to the proximal chamber.

In the case of obstruction of either or both catheters the application of additional pressure to the steps outlined above for checking operation of the devices will act to flush obstructions from the catheter. In all but the most severe obstructions this procedure readily opens the catheters to How, thus eliminating any need for corrective surgery.

Thus there has been described a hydrocephalus shunt assembly equipped with a novel flushing and patency checking device. The device provides for both the checking of patency and flushing in both directions. Since the flushing device is relatively fiat and is backed by the skull of the patient, and the catheters extend therefrom in the plane of the flushing device, positive pressure for flushing may be easily applied without any tendency of the device to move as pressure is applied, thus minimizing any discomfort. Besides acting as flushing and patency checking devices, the blister-shaped members covering the chambers also provide an ideal point for injection of medica tion or irrigating fluids since small punctures in the chambers cause no ill effects on the function of the device and tend to reseal themselves.

A further modification of the device which is often desirable is the inclusion of radio opaque pigment in the formulation used for forming the device. This provides a ready means for checking position of the device by use of X rays. If desired, tissue permeable material may be adhered to surfaces of the device to provide better anchor- Obviously, other variations, modifications, and attendant advantages of the device disclosed herein will become obvious to those skilled in the art from a consideration of the foregoing. It is, therefore, to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

That which is claimed is:

1. In a surgically implantable device for the treatment of hydrocephalus comprising a ventricular catheter for introduction into the brain ventricle and an outlet catheter 5 the improvement comprising:

a flushing device interposed between said catheters comprising a substantially flat continuous backing member adapted to overlie the skull,

a pair of chambers carried by said backing member, each of said chambers being defined by said backing member and a flexible resilient blister-shaped covering member juxtaposed on said backing member,

inlet means interconnecting said ventricular catheter and one of said chambers,

outlet means for interconnecting said outlet catheter and the other of said chambers, and

a tubular member interconnecting said two chambers and extending from the approximate center of one of said chambers to the approximate center of the other of said chambers, whereby pressure applied to collapse the blister-shaped covering member of either of said chambers also acts to collapse the end of said tubular member which lies in the collapsed chamber.

2. The invention as defined in claim 1 wherein said chambers further comprise recesses in said backing memher.

3. The invention as defined in claim 1 wherein said catheters are connected to said baseplate substantially in the plane of said baseplate.

4. The invention as defined in claim 3 wherein all parts of said device are made of silicone rubber.

Hakim, Valve System for Ventriculo-Atriostomy, Cordis pamphlet, Oct. 5, 1965, pp. 3, 6-8.

DALTON L. TRULUCK, Primary Examiner.

US. Cl. X.R. 128-232 

